Make the Onion Obsession Compound Butter. Using a stand mixer fitted with the paddle attachment, or in a medium bowl using a hand-held mixer, combine the room temp butter, Onion Obsession Spice, salt and pepper, to taste.
Set aside or refrigerate until needed. (If refrigerated, bring to room temperature until just softened enough to spread before using.)
Make the Onion-Bacon. Preheat the oven to 425 degrees F. Line a large rimmed baking sheet with foil for easy clean up. Place a wire (cooling) rack over the baking sheet.
Lay the bacon slices in a single layer on the rack. Set aside.
In a small bowl, combine the Sweet Onion Sugar, brown sugar, paprika, crushed red pepper, salt and pepper to taste.
Sprinkle and press the mixture onto both sides of the bacon slices.
Bake in the preheated oven for 20 to 30 minutes, or until crispy (or to your preferred doneness).
Roast the veggies. Either prepare another large rimmed baking sheet with foil or drain off the bacon grease well and wipe gently from the previously used baking sheet. Be careful; it will be hot. Scatter the vegetables on the baking sheet, drizzle with oil, sprinkle with salt and pepper (or your favorite seasoning).
Bake the veggies in the oven for 20 to 30 minutes, depending on how soft you want them. I bake for 26 minutes. Check the vegetables at 20 minutes for too much browning. Remove them from the oven.
Spread a thin layer of the compound butter on one side of each slice of bread. Turn both the bread slices over. Divide the vegetables amongst the sandwiches. Top with cheese, bacon, and the top slice of bread, butter side up.
Heat a shallow pan or skillet over medium-low heat. Add the sandwiches (you may need to do this in batches).
“Grill” the sandwiches just until lightly golden brown, flip and “grill” them again on the other side until lightly golden brown.
Serve while still warm and delicious.